In marine propulsion devices disposed outside of the hull, their casing during cruising splashes a mixture of water film and droplets in the upward direction from the surface of the water. In order to prevent the splashed water from impinging upon the upper portion of the casing, a splash plate is provided on the casing so that it extends from the front surface (frontwardly-facing surface) of the casing to the side surfaces of the same, thereby to deflect the upwardly directed splashes of water downwardly.
However, a casing of some cross-sections deflects the splashed water forwardly. Then a conventional splash plate fails sufficiently to prevent a violent frontward deflection of splashes. As a result, splashes of water are scattered upwardly in the frontward direction, onto the stern, and thereafter are scattered upwardly. The splashed water then can enter the interior of the hull or fall onto the engine or onto electric parts in the engine cowling.
In order to obviate the above-explained drawback of the prior art, it has been proposed to increase the length of the frontwardly projected portion of the splash plate. However, there is a practical limit to the length of the forwardly projected portion of a splash plate, because it is necessary to avoid mutual interference between the splash plate and the stern of the boat, and to meet the requirements for strength and size.
An object of the present invention is to provide a splash plate for marine propulsion devices, which can reliably prevent the splashes of water from scattering in the upward direction, and without increasing the length of the forward projection of the splash plate.